Hyperthermia occurs when an individual has a high body temperature of at least 104 degrees F. Severe hyperthermia can reach as high as 108 degrees F. The condition occurs when the body can no longer release heat by the usual methods of sweating, breathing, and blood flow to the skin. For example, if a person is working out on a hot, humid day or sitting in a hot room, perspiration may accumulate on the skin. The sweat must evaporate for cooling to take place. If the temperature outside the body is hotter or more humid, the sweat can't evaporate, and the internal organs start to heat up. This can lead to very serious symptoms and even be fatal. Older adults, very young children, and those with compromised immune systems are especially vulnerable to the dangers of hyperthermia.
In addition to the environment, heat illness can be brought on by dehydration, wearing clothing that traps perspiration, and drinking alcohol. Layers of tight, heavy clothing should not be worn for exercise. People who are not used to hot and humid conditions are also more prone to heat illness, especially if they exercise vigorously.
The symptoms of hyperthermia progress from mild to severe depending on how overheated the body becomes. Symptoms may come on suddenly or develop over a long period. Sweating takes water and salts (electrolytes) out of the body resulting in dehydration. Thirst may accompany by the first stage, which is called heat stress. Mild symptoms may include such as a headache or muscle cramps.
Heat stress is a mild form of hyperthermia, but any symptoms must be paid attention to and treated promptly. During heat stress, the body temperature begins to rise, and perspiration does not relieve the discomfort. Other symptoms include dizziness, weakness, nausea, and headache. When these sensations arise, it is best to find a cool spot in the shade if outdoors, or to an air-conditioned room, and rest. Drink water or a sports drink with electrolytes. If symptoms worsen, get medical help.
Someone who works or exercises for long periods in the sun can develop heat fatigue. It is more than just feeling uncomfortable and thirsty. Lack of concentration may set in, and possibly loss of coordination. People new to hot, humid environments should take their time getting used to the new climate. If symptoms develop, the individual should increase hydration and move to a cool, preferably air-conditioned location. Heat syncope or fainting is more serious. The person may suddenly feel dizzy or lightheaded and faint while working out in the heat. The blood pressure drops, and too little blood reaches the brain. A person taking beta-blocker medications for high blood pressure is at increased risk. If possible, someone experiencing dizziness or lightheadedness should immediately stop all activity and try to cool down by drinking water or electrolyte-containing sports drinks. Lying down with the feet up ensures more blood is reaching the brain.
Heat exhaustion is a serious hyperthermic condition that requires medical attention. As with the previous conditions, the body is no longer able to cool itself off. The same symptoms also apply here. Profuse sweating, dizziness, thirst, lack of coordination, and trouble concentrating may occur. The pulse becomes rapid, and the skin becomes cool and clammy. Some people also experience general weakness, nausea, vomiting, and fainting. This is the last stage before heat stroke becomes a possibility. Rest and drink fluids immediately. Ask for help, or call 911.
Heat stroke is the deadliest stage of hyperthermia. Several athletes have died on the playing field due to overexertion and heat stroke. Symptoms already mentioned continuing to build up if the individual does not receive treatment. People with heat stroke develop very high body temperatures, rapid or strong pulse or heart rate, hot, red, or dry skin, fast, deep breathing, reduced perspiration, headaches, confusion, disorientation, blurred vision, irritability, mood changes, and fainting or loss of consciousness. Severe symptoms such as seizures, organ failure, coma, muscle damage, and kidney damage can follow. Immediate transportation to the hospital is essential for people with heat stroke.
Heat edema is swelling in the lower legs, ankles, and hands that develops when someone has been standing or sitting too long in the intense heat. Fluid can accumulate in these areas if the individual is not used to the high temperature or humidity. Heat edema may resolve by itself as the body adjusts to the heat. Propping up the feet helps, along with hydration and removing to a cooler area. Another hyperthermic condition is heat rash, which consists of small red bumps or pimples under sweaty clothing. These generally clear up when the individual cools off or changes clothes.
Self-treatments such as resting in a cool place and rehydrating can ease mild symptoms such as fatigue, cramps, and headache. Other measures include loosening and removing unnecessary clothes, placing a cool, wet washrag or cloth on the forehead, running cool water on the wrists for 30 seconds, lying down, and taking a cool bath or shower. People with any type of hyperthermia should not resume the problematic activities or return to the heat until all symptoms resolve; this should occur within an hour, or more serious conditions could develop.
In cases of heat stroke, it is vital to get the person to the hospital. In the meantime, the individual should move to a cool area, if possible. He or she can sip water only if fully conscious, and should not eat food. If someone is nearby to assist, they can remove excess clothing, place cool, wet cloths on the skin, and ice packs under the arms or on the groin, where the blood is close to the skin.
Hyperthermia treatment may involve submersion into ice water to lower the body temperature quickly, or misting the skin with cold water. Medical professionals may also have special cooling blankets in which patients can be wrapped. Once the patient begins shivering, the body temperature should start to rise, and special medications can treat this side effect.
This site offers information designed for educational purposes only. You should not rely on any information on this site as a substitute for professional medical advice, diagnosis, treatment, or as a substitute for, professional counseling care, advice, diagnosis, or treatment. If you have any concerns or questions about your health, you should always consult with a physician or other healthcare professional.